Choose an Isolation Level

The ANSI SQL standard defines four levels of isolation for transactions. Each isolation level specifies the kinds of actions that are not permitted while concurrent transactions are executing. Higher levels include the restrictions imposed by the lower levels.

You can set the isolation level for your session by using the transaction isolation level option of the set command. You can enforce the isolation level for only a single query as opposed to using the at isolation clause of the select statement. For example:

set transaction isolation level 0